A conventional electrical connector for connecting an inner surface of a wall of a sealed chamber with an outside surface of the wall is disclosed in Japanese Patent Application No. 2013-37890. A base member of epoxy resin containing glass is disclosed for closing an opening in the chamber wall of the sealed chamber. A metal plate is positioned on a side of the electrical connector, and the entire circumferential edge of the metal plate is soldered to the chamber wall upon mounting the electrical connector.
However, since the entire circumference has been soldered to the wall, when a failure occurs in the electrical connector or the soldered portion, replacement of the electrical connector is difficult, often requiring the whole chamber having the wall to be discarded.
Japanese Patent Application No. 2010-135536 discloses a load lock apparatus having an elastic plate and an O-ring used to seal openings in walls. The elastic plate can be easily removed by detaching a clamp member and a screw for fixing the elastic plate to the chamber wall, allowing the electrical connector to be easily replaced.
Combining the O-ring approach used in JP 2010-135536 with the conventional electrical connector described in JP 2013-37890 is highly desirable, because the conventional electrical connector could easily be removable without having to discard the whole chamber having the wall when the connector fails.
However, when sealing is performed using the O-ring, industrial standards such as JIS Standards require a member making contact with the O-ring to have a predetermined surface roughness of at least Ra 3.2 μm or less. Since the electrical connector described in JP 2013-37890 A is made of epoxy resin containing glass, it is extremely difficult to form a surface of the electrical connector such that the surface has the predetermined surface roughness required by the industrial standards.
Therefore, there is a need for a flat electrical connector assembly which is easily replaceable, where a predetermined surface roughness can be obtained, and a mounting structure thereof.